Me I like having a physic keyboard when I want it or not..just like the n810 and n900..so I'm personally biased to either:
A-thinkpad x convertible tablet series
or
B-toshiba portege m convertible tablet series
they can be got cheaper than the 3 you mention (the lowly m200 or the x60 are great devices ...a little older and slower but good design...and still perform admirably) .or more expensive (ie. toshiba portege m780 or thinkpad x230t ......a wicked model I love...came out last year...)
they perform admirally with win or a wide range of linux distros...
much more user friendly when it comes down to keyboard usage..
If what you want... is to get what you need to ...done...
and without frustration...get a portege m series or thinkpad x series...When you pull one out ...it will turn heads. Also the depreciating value in laptops or tablets is much different than in convertible laptops ...convertibles hold their monetary value much longer...
However ...If you want to look chic and fit in ...get what everyone else uses.